1. Field of the Invention
The present invention concerns techniques for remotely diagnosing a network device over a local area network (LAN), for example, from a workstation on the LAN which is located remotely of the network device. More specifically, the invention concerns transmission from the workstation of specialized dump/debug network communication packets which are responded to by the lowest network device driver on the network device in an interrupt-disabled state.
2. Description of the Related Art
With increasingly wide usage of computerized local area networks (LANs), it is becoming more and more common to connect peripheral devices such as printers and scanners to such LANs so as to permit those peripheral devices to be accessible from any workstation or computer on the LAN. While in the past it has been necessary to provide a dedicated personal computer such as an IBM-PC or PC-compatible computer so as to interface between the peripheral device and the LAN, it has more recently been proposed to provide such interface functions on a single interface board connected to the peripheral. U.S. Pat. No. 5,323,393 to Barrett, et al., and U.S. application Ser. No. 08/409,034, now U.S. Pat. Nos. 5,724,555 "Network Interface Board For Digital Copier", both assigned to the same assignee as the present application, both describe examples of such interface boards.
At the same time, the LANs themselves have become more complex, particularly with regard to the different kinds of network communications carried thereon. For example, it has recently become possible for a single LAN to carry on several different types of communications at the same time, for example, Novell-based communications between IBM-compatible personal computers, TCP/IP-based communications for UNIX-type workstations, and AppleTalk-based communications for Apple-type computers such as Maclntosh. Thus, in order to interface between such a complicated LAN and a peripheral device, the interface board for the peripheral device must also be complicated so as to be able to provide a robust platform over which network communications to the peripheral can be carried out.
In the real world, however, not every single eventuality on the network can be foreseen. These unforeseen eventualities can cause problems to occur on the interface board which make the interface board non-operational for reasons which need to be ascertained. While a memory dump or debug facility may assist in diagnosing those reasons, since the interface board is non-operational it is difficult to obtain a memory dump or to initiate a debug facility.
Ser. No. 08/336,102, "Low-Cost Serial Port", proposed a serial port physically located on the interactive board which functioned with the non-maskable interrupt of the board's microprocessor so as to permit dump and/or debug facilities. The proposed serial port effectively allows diagnosis of the reasons as to why the interface board has become non-operational. However, room for improvement is needed with respect to at least two areas.
First, since the proposed serial port of Ser. No. 08/336,102 is physically co-located with the interface board, the technician diagnosing problems on the interface board must also be physically co-located with the interface board. Second, since the serial port offers only serial cnmmunications with the interface board, transmission of large amounts of data, such as might be encountered in a full memory dump, consumes an unduly lengthy period of time.
Thus, a need exists for dump and/or debug facilities for a network interface board which can be carried out remotely of the interface board and which can carry large amounts of data in a short amount of time.